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when toggle format what by license comment
Jun 8, 2010 at 14:42 history edited François G. Dorais CC BY-SA 2.5
addendum
Feb 26, 2010 at 14:02 history edited François G. Dorais CC BY-SA 2.5
improved formatting
Jan 30, 2010 at 18:07 comment added François G. Dorais There is a little syntactic trick involved. Any Sigma-cut in a Sigma-definable initial model is also a Sigma-cut in the larger model by constraining the witnesses to existential quantifiers to stay within the smaller model. Therefore, when I is the minimal Sigma-cut, the initial model A_I has no proper Sigma-cut.
Jan 30, 2010 at 16:30 comment added Mike Shulman Thanks! I'm not too familiar with arguments involving lots of Σs and Πs, so I need some help understanding this. I think I follow the Σ-cut lemma, but why does a minimal Σ-cut give a model of KP⁰ that satisfies Σ-induction?
Jan 27, 2010 at 4:50 history edited François G. Dorais CC BY-SA 2.5
typos and a small clarification
Jan 27, 2010 at 3:57 history answered François G. Dorais CC BY-SA 2.5